Electrostatic smoking device



1951 K. w. MHCKENZIE EIAL ,565, 54

ELECTROSTATIC SMOKING DEVICE Filed Sept. 20, 1947 3 Sheets-Sheet lSOURCE OF DIRECT +VOL TAGE FROM SMOKE To EXHAUST GENERATOR Q 51.0 wen MQv lzwsurons KENNETH wMAckmz/E GLENN E. ANDREWS sv z gii;

1951 K. w. M KENZIE ETAL 2,565,454

ELECTROSTATIC SMOKING DEVICE Filed Sept. 20, 194"! 3 Sheets-Sheet 2 FROMSMOKE GENE/FA TOR BLOWER lnvsumks 'KslvusmwMAckelvzle GLENN E. AND/25m;

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Patented Aug. 21, 1951 ELECTROSTATIC SMOKING DEVICE Kenneth W.MacKenzie,

Glenn E. Andrews, And Raytheon Manufact Newton Highlands, and over,Mass., assignors to uring Company,

Newton,

Mass., a corporation of Delaware Application September 20, 1947, SerialNo. 775,266

11 Claims. (Cl. 99-261) This invention relates to electrostatic smokingdevices, and more particularly to apparatus for electrostaticallydepositing or precipitating smoke particles ontothe surfaces of massesof food, such as meat or fish, which it is desired to smoke.

An object of this invention is to devise apparatus for smoking food, bythe use of which food may be smoked in a very much shorter time thanwith prior smoking equipment, with no sacrifice of quality.

Another object is to devise a smoking device by the use of which a veryuniform and sufficiently dense deposit of smoke may be produced on thefood articles being smoked.

A further object is to provide an electrostatic smoking apparatus whichrequires only a relatively low voltage.

A still further object is to devise electrostatic smoking equipmentwhich ispractical, eflicient, and simple in design.

The foregoing and other objects of the, invention will be bestunderstood from the following description of some exemplificationsthereof, reference being had to the wherein:

Fig. 1 is a vertical section through a complete ionizer and collectorcell assembly of one type of electrostatic smoker constructed inaccordance with the invention;

Fig. 2 is a horizontal section taken on line 2-2 of Fig. 1;

Fig. 3 is a perspective view of the ionizer and collector cell assemblyof Fig. 1 but with the shelf unit removed;

Fig. 4 is a perspective view of the shelf unit of Fig. l;

Fig. 5 is a vertical section through a modified accompanying drawings,"

, mediate the tubular electrodes 8,

form of smoking apparatus according to the invention; and

Fig. 6 is a section Now referring to the drawings. ticularly to Figs.1-4 thereof, the numeral I generally designates the active orsmoke-precipitating portion of an electrostatic smoking apparatus. saidportion consists of an ionizing structure 2 and a collecting structureI.

The structure 2 is an ionizer of the construc tion disclosed and claimedin the copending' application of Kenneth W. MacKenzie, Ser. No. 678,145,filed June 20, 1946, now abandoned. Structure 2 comprises a rectangularframe of metal providing side walls 4 and 5 and upper and lower endwalls Ii and 1, respectively. A'plurality of substantially horizontaltubular electrodes 8 are secured in spaced parallel relation through theside-walls l and 5. A plurality of horizontal fine wire electrodes 9 aresupported in spaced parallel relation to the tubular electrodes 8 by agrill or high voltage framework indicated generaltaken along line 6 90fand more ar-- 'tions of said rods.

crossbar 23, parallel to bars I5 and I6, welded to 'being parallel tothe ly at Ill. The metallic framework I 0 and the ionizing wires 9supported thereby are insulated Two of the insulators II are secured bybolts I2 to one of the tubular electrodes 8 adjacent one end of thestructure 2, and a second pair of insulators II are secured by similarbolts to another of the tubular electrodes 8, preferably at the oppositeend of the structure 2.

The outer ends of the insulators II each have an inwardly-curvingchannel iron I3 suitably secured thereto, as by a bolt I4. The inner endof each of the channel irons I3 is welded to the framework ID, in thisinstance to the angle irons I5 and I6 forming the upper and lowerhorizontal crossbars of the framework.

At their left and right ends the crossbars I5 and I6 have welded theretoleft and right vertical bars I! and I8, respectively. The bars I1 and I8have secured therethrough a plurality of paired aligned supporting rodsI9 which are of suflicient strength to support the fine wire electrodes9 therebetween with great rigidity, but which are sufficiently flexibleto maintain the wire electrodes under tension. The rods or pins I 9 arespaced to support the fine wire electrodes 9 at points interand inparallel relation thereto.

An intermediate vertical bar- 20, parallel to bars I! and I8, carries aplurality of spaced rods 2| which terminate in hooked portions 22. Therods .2I are positioned in alignment with coacting pairs of left andright pins I9 to contact the fine wire electrodes 9 at pointsintermediate their length to prevent vibration thereof. Rods 2| are ofsuch length that wires 9 pass through the hooked por- An intermediatehorizontal the outer vertical bars I! and I8 and the intermediatevertical bar 20, may be provided to give the supporting framework In agreater rigidity.

I The rods I9 are attached to the left and right bars I! and I 8 in anysuitable manner, for example in the manner described in theaforementioned MacKenzie application. The ends of the fine wireelectrodes 9 may be secured to rods I 9 in any suitable manner, such asthat disclosed in the MacKenzie application above referred to.

A plurality of spaced horizontal parallel metal-- lic plates 24 aremounted on the ionizer high voltage framework Ill. These plates are madeof rather thin metal, and are rectangular in outline, with the majordimension of each rectangle wires 9' and to the longitudinal axis oftubular electrodes 8. A-sufiici'ent number of plates are provided tosubstantially fill the entire space between opposite channel irons I3,the spacing between the adjacent plates being determined as describedmore in detail hereinafter. Plates 24 are preferably secured to frame Inby flanging said plates at one side and welding the flanges to the barsl1, l8, and 20. Collector plates 24 are mounted on that sideof bars 11,I8, and 20 which is opposite from wire electrodes 9; said plates aretherefore mounted externally of the ionizing structure 2; the saidplates are a component of the collecting structure 3. Plates 24preferably have a length somewhat greater than that of wire electrodes9.

A food-supporting shelf assembly, consisting of a plurality of spacedhorizontal parallel metallic shelf plates 25 mechanically joinedtogether by a pair of opposite vertical metallic transverse end wallmembers 26, constitutes the grounded portion of the collecting structure3. Shelves 25 are rectangular in outline and have substantially the samelength and width as plates 24. The shelves 25 are so spaced that, whenthe shelf assembly or unit is in operative position with respect toplates 24, the shelves 25 will be located intermediate the said plates;the shelf assembly is movable with respect to the remainder of theapparatus from the operative meshed position shown in Fig. 1 to theloading position shown in Fig. 4, in which position said shelf assemblyis entirely separated from the rest of the apparatus and is in aposition enabling masses of food to be placed on and removed from theshelves without danger.

The food to be smoked, shown as fish in metal cans 21 only by way ofexample, is placed on the shelves 25 and is supported thereby, sincesaidshelves are horizontal when the apparatus is being used for smoking.Plates 24 are mechanically and electrically connected to the highvoltage frame ill of the ionizer 2, and are therefore at the samepotential as said frame. The frame I0 is connected, by means of a cableor lead 28, to the positive terminal 29 of a suitable source 30 of highdirect voltage, the negative terminal 3| of which is grounded as at 32.Therefore, wire electrodes 9 and plates 24 are at a high p itivepotential with respect to ground, on the order of 12,000 volts, forexample. The frame 4-1 is grounded at 33, so that the tubular electrodes8 are also at ground potential. The, end wall members 26 of the shelfassembly are grounded as at 24, so that shelves 25, and the metal cans21 of food thereon, are at ground potential.

As stated above, the unit consisting of the shelves 25 is removable sothat it can be loaded with cans of fish and then slid into place, asshown in Fig. 1, for the smoking process. In use, the apparatus ismounted so that the wire electrodes 9 of the ionizer extendsubstantially horizontally and perpendicular to the paper in Fig. 1. Itis to be understood that the unit I is mounted in a suitable groundedenclosure, preferably made of metal,- and smoke-laden air is supplied tothe enclosure and is caused to flow therethrough inQthe direction of thearrows in Fig. 1, so that such air passes between the electrodes 8 and 9before passing between the electrodes 24 and 25. The smoke generator andexhaust blower for producing this flow of smoke-laden air are not shown.

The frame 4-1 is preferably directly mounted in and electricallyconnected to the grounded enclosure, with the .wire electrodes 9extending horizontally. Plates 24, being parallel to wires 9. aretherefore also horizontal. The shelf unit. when loaded with the food tobe smoked, is slid into place with the shelves 25 meshing between plates24 and extending horizontally, the lower ends of the end members 26resting on the lower 4 interior wall of the enclosure in order to groundshelves 25 and to support them in position,

Each of the grounded elements 25 of the collecting structure 3 ispositioned between a pair of adjacent positive collector plates 24, asshown. The spacing between adjacent shelves 25, and also betweenadjacent plates 24, is made such that, taking into account the magnitudeof the voltage between plates 24 and 25, the depth of cans 21, and thevelocity of air fiow through the enclosure, there will be a maximumprecipitation of smoke on the fish and at the same time noshort-circuiting discharge will occur between any of the adjacent plates24 and 25. If source 30 produces 12,000 volts, it has been found that adistance on the order of inch or greater, between the top of each can 21and the bottom of the plate 24 next thereabove, and between the top ofeach of the inner plates 24 and the bottom of the shelf 25 nextthereabove, is satisfactory.

There is a high voltage between the wire electrodes 9 and the tubularelectrodes 8 of the ionizing structure 2, and these pairs of adjacentelectrodes cooperate with each other, by means of the ionizing dischargetherebetween, to charge, with a potential which is positive with respectto ground or the negative terminal of the source 30, the finiteparticles of sol d matter, or smoke particles, in the atmosphere withinthe enclosure around the ionizing structure 2.

As these ionized smoke particles travel on through the ionizingstructure 2, they enter the region of the collecting structure 3. Inthis region, the electrostatic field between adjacent plates 24 and 25,together with the polarity of the charge on the particles, causes saidparticles to move to and be deposited upon the grounded elements of thecollecting structure. The fish to be smoked, being in the metal cans 21which are in contact with the metal grounded shelves 25, become in turngrounded elements; the smoke particles move to the fish and aredeposited thereon.

It has been found that, by the use of the electrostatic smokingapparatus of this invention, food may be smoked in a very much shortertime than when prior art equipment is used, with no sacrifice of qualityof the smoked product. For example, the smoking time may be reduced fromapproximately eight hours to approximately twenty minutes.

By using the configuration of ionizer and collector cell disclosedherein, with the positive collector plates mounted directly on theionizer high r voltage frame, the distance from the ionizer 2 to thecell 3 is minimized and the positively charged smoke particles losealmost no charge in traveling the very short distance from the ionizert0 the collector plates. Therefore, the apparatus of this inventionutilizes the smoke very efilciently. and a very dense and uniformdeposit of smoke may be produced on the food.

It is within the scope of this invention to utilize, as the groundedelectrodes, wire screen for the supporting shelves instead ofimperforate pieces of metal. By so doing, and if the cans 21 areeliminated, uncanned fish can be placed on the screens and smoked onboth sides, Large fish can be smoked in this way, since the groundedelements of the collector cell are perforate in thiscase so that smokecan be deposited on the bottom surfaces of such fish.

Now referring to Figs. 5 and 6, these figures show a modified form ofelectrostatic smoking apparatus, by means of which meat, such as bacon,ham, or sausage, for example, may be smoked in a continuous manner. Inthese figures, partssimilar to those in Figs. 1-4 are given the samereference numerals; Figs. 5 and 6 show the apparatus on an enlargedscale.

A chamber or enclosure 35, having open upper and lower ends, is suppliedwith smoke-laden air through its lower end and is exhausted through itsupper end, so that smake flows upwardly through said chamber. The smokegenerator and exhaust blower for producing this flow of smokeladen airare not shown. The flow of smoke through enclosure 35 is in thedirection of the arrows in Fig. 5.

An ionizing structure 2, which is quite similar to that of Fig. 1 exceptthat the plates 24 are omitted from high voltage framework l8 and exceptthat the sets of angle irons I5, I6, 23 and I1, i8, 28 are interchangedwith respect to each other from their positions in Fig. 1, is mountedhorizontally in the lower end of chamber 35 by any suitable means, as bymeans of a plurality of supporting irons 36 fixed to the interior wallsof said chamber, the main outer or grounded frame of the ionizingstructure resting on said irons. The ionizing structure is preferablymounted so that the insulators H extend downwardly from the main outeror grounded metal frame.

Above structure 2 is mounted a plurality, here shown as three in number,of parallel spaced metallic plates 31. These plates are thin and Fig. 1,since plates 31 are located in the path of.

to be smoked, in a continuous manner'between adjacent pairs of plates 31in the direction of the arrows 43. In order to allow for passage of thefood and the conveying means through chamber 35, while at the same timepermitting continuous loading and unloading of the food from theconveyor, a pair of apertures 50 are provided through each opposite endwall of chamber 35, these apertures being of suflicient size to permitthe passage therethrough of the conveyor loaded with food, these fourapertures being arranged in two oppositely-disposed aligned pairs, onepair of apertures being aligned with each of the chains 5|.

Two spaced parallel endless chains 5| are provided, both chains beingpreferably of the flex-, ible roller link type. Each of said chains is Idriven by a pair of oppositely-disposed sprocket wheels 52, the wheelsof each pair being mounted for rotation at opposite ends of chamber 35,outside the same and inside the projections of the sides of thecorresponding paired aligned apertures 50. The two sprocket wheels atone end of chamber 35 are secured to a common shaft 53 and are rotatedat any suitable speed by a motor (not shown), through a drive pulley 54are mounted vertically, said plates having a length substantially equalto that of the ionizing structure. The plates 31 are mounted in chamber35, the two outer plates being supported therein by means of a pluralityof horizontallyextending insulators 38 each secured to one end to one ofthe inner side walls of chamber 35 and each secured at its opposite endto one of said two outer pla'tes31. In order to maintain the centralplate 31 in position in chamber 35 and to maintain plates 31 properlyassembled and spaced with respect to each other, a plurality of metallictie rods 39 are provided near the bottom edges of plates 31, each tierod passing through all three plates by means of suitable alignedapertures provided therethrough, andpreferably being secured to allthree plates. A plurality of tubular metallic spacing members 40 areprovided, each surrounding a corresponding portion of one of the tierods and each member 40 having its opposite ends bearing against, andsecured to, a pair of adjacent plates. Thus, members 40 function toproperly space the central plate 31 from the two end plates 31, whilerods 38 hold the assembly together. Plates 31 are all of equal "area,and have their upper and lower ends positioned in the same horizontalplane.

Plates 31 are insulatingly mounted in chamber 35 by means of insulators38, as above described, and are connected, as schematically indicated inFig. 5, by means'of a lead 4|, to the positive or ungrounded terminal 42of a high voltage direct current source 43,, the negative terminal 48 ofwhich is grounded at 45. Chamber 35 is ordinarily grounded, as are thetubes 8 of the ionizing structure 2, as by means of lead 45, while thefine wires 9 of structure 2 are connected to lead 4| and positive sourceterminal 42. The lower ends or edges of plates 31 are located justslightly above the upper edge of ionizing structure 2 and, with saidplates connected to the positive ungrounded terminal 42 of the source,function similarly to the collecting plates 24 of mounted on said shaft.

A plurality of outwardly-projecting hooks 55 are secured, as byriveting, to each of the chains 5| at uniform intervals therealong.Although a hook is shown in the drawin as being fastened I to each andevery link of the chains, it is to be understood that the hooks may bespaced any desired number of links apart.

The paired sprocket wheels for each chain are positioned, from left toright in Fig. 6, substantially midway between the corresponding pairs ofadjacent plates 31. The chains 51 are spaced any suitable distance aboveplates 31, and hooks 55 have a length such that, when the masses of food48 are hung' thereon, said masses will be so horizontally positionedthat theywill be conveyed by one of the chains 5| through chamber 35between adjacent pairs of plates. A separate line or series of foodmasses may be hung on each chain 5| at the left end of the chamber inFig. 5, and the two separate lines of food are V sprocket wheels 52.

then passed simultaneously through chamber 35, each line passing betweenits corresponding adjacent pair of plates 31, after which the lines maybe removed from the hooks at the right end of the chamber in Fig. 5. a

Food masses 48, such as hams, sides of bacon,

or strings of sausages, for example, are hung by means of metallicsupporting means from metal hooks 55. so that said masses areelectrically connected to chains 5| and therefore also to grounded as at55, so that masses 43 are connected to the grounded or negative terminal44 of the high voltage source 43.

The grounded masses of food, together with the high voltage plates 31,function as a collector cell for the ionizedv smoke particles which areprovided in the space above ionizing structure 2. The smoke particlesare charged positively by the ionizing structure 2, then passingupwardly into the field between plates 31 and rounded food masses 48,which field causes such particles to move to and be precipitated on theThe sprocket wheels aregrounded or negative food masses 48. Therefore,

- when the apparatus is in operation, two lines of chains on which theyare hung causing movement of said masses through the collector cellregion of the smoke precipitatingapparatus; the smoked food may beremoved from the hooks at the right end of the chamber in Fig. 5.

In order to support the weight of the loaded chains, and to properlyguide the food masses between the adjacent pairs of plates 31, twospaced parallel elongated guiding tracks or channels 51 are utilized,each having a length substantially equal to that of the chamber 35, eachextending through the interior of said chamber, and each beinglongitudinally aligned with the lower sweep of a corresponding one ofthe chains Each of the tracks 51 is supported from an adjacent innerside wall of chamber 35 by a separate supporting member 58. Each of thetracks 51 is substantially of inverted U-shape, but each has a pair ofopposed horizontal inwardly-extending flanges at its lower end, on theupper surface of which the corresponding chain slides throughout thetravel of the lower sweep of such chain through chamber 35. The spacedends of the horizontal flanges of each track in effect provide alongitudinal slot therebetween through which the hooks 55 extend. Eachof the tracks 51 is open at its ends to allow entry of the correspondingchain thereinto and egress of such chain therefrom. The interior of eachtrack is of suflicient size to accommodate the corresponding chain 51therein; with such chain contacting only the bottom wall of the track,or the upper surface of the horizontal flanges thereof.

If desired, rollers could be provided inside the tracks 51 or on thechains, to provide rolling rather than sliding contact between thechains and the corresponding tracks. It is to be understood that eachgrounded mass of food 48 passes between a pair of high voltage positiveplates; said mass acts as the negative collector electrode and issmoked. It is desired to be made clear that the showing in Figs. 5 and 6is on a greatly enlarged scale, the distance between the positive plates31 and the food 48 actually being approximately inch.

Of course, it is to be understood that this invention is not limited tothe particular details grounded metallic frame and a high voltagemetallic frame insulatingly mounted on said grounded frame, each of saidframes having electrically connected thereto electrodes which cooperatewith those of the other frame to charge with a predetermined polarityfinite particles of solid matter suspended in the atmospheretherearound; said collecting structure including a grounded electrodeand a high voltage electrode, said high voltage electrode being mountedon said high voltage frame externally of said ionizing structure andsaid grounded electrode comprising at least in part means adapted tosupport a mass'of food to be smoked. v

2. Apparatus for smoking masses of food, comprising an ionizingstructure and a collecting structure; said ionizing structure includinga grounded metallic frame and a high voltage metallic frame insulatinglymounted on said grounded frame, each of said frames having electricallyconnected thereto electrodes which cooperate with those of the otherframe to charge with a predetermined polarity finite particles of solidmatter suspended in the atmosphere therearound; said collectingstructure including a plurality of spaced grounded electrodes and aplurality of spaced high voltage electrodes intermediate said groundedelectrodes, said high voltage electrodes being mounted on said highvoltage frame externally of said ionizing structure.

3. Apparatus for smoking masses of food, comprising an ionizingstructure and a collecting structure; said ionizing structure includinga grounded metallic frame and a high voltage metallic frame insulatinglymounted on said grounded frame, each of said frames having electricallyconnected thereto electrodes which cooperate with those of the otherframe to charge with a predetermined polarity finite particles of solidmatter suspended in the atmosphere therearound; said collectingstructure including a plurality of spaced grounded electrodes and aplurality of spaced high voltage electrodes intermediate said groundedelectrodes, said high voltage electrodes being mounted on said highvoltage frame externally of said ionizing structure, said groundedelectrodes being adapted to electrically contact said masses of food.

as described above, as many equivalents will suggest themselves to'those skilled in the art. For example, different voltages could be usedfor ionization and collection if desired, in which case the collectorplates 24 would be insulatingly mounted on the high voltage frame I0.Also. the ionizer 2 could be turned around if desired, in which eventthe collecting structure 3 would be supported separately. In addition,the plates 24, instead of being parallel to shelves 25, couldibeinclined in the direction of air flow in such a way that the spacebetween adjacent plates and shelves would decrease as one proceededalong thedirection of air flow, this being done, if desired to give amore uniform precipitation of smoke. Other variations will suggestthemselves. It is accordingly desired that the appended claims be givena broad interpretation commensurate with the scope of this inventionwithin the art.

What is claimedis:

1. Apparatus for smoking masses of food, comprising an ionizingstructure and a collecting structure said ionizing structure including a4. Apparatus for smoking masses of food, comprising an ionizingstructure and a collecting structure; said ionizing structure includinga grounded metallic frame and a high voltage metallic frame insulatinglymounted on said grounded frame, each of said frames havingelectricallyconnected thereto electrodes which cooperate with those of the otherframe to charge with a predetermined polarity finite particles of solidmatter suspended in the atmosphere therearound: said collectingstructure including a plurality of spaced grounded horizontally-mountedplate electrodes and a plurality of spaced high voltagehorizontally-mounted plate electrodes intermediate said groundedelectrodes, said high voltage electrodes being mounted on said highvoltage frame externally of said ionizing structure, said groundedelectrodes being adapted to have the masses of food to be smoked restedthereon.

5. Apparatus for smoking masses of food, comprising an ionizingstructure and a collecting structure; said ionizing structure includinga grounded ,metallic frame and a high voltage metallic frameinsulatingly mounted on said grounded frame, each of said frames havingelectrically connected thereto electrodes which cooperate with those ofthe other frame to charge with a predetermined polarity finite particlesof solid matter suspended in the atmosphere therearound; said collectingstructure including a plurality of spaced grounded horizontally-mountedplate electrodes and a plurality of spaced high voltagehorizontally-mounted plate electrodes intermediate said groundedelectrodes, said high voltage electrodes being mounted on said highvoltage frame externally of said ionizing structure, said groundedelectrodes being mechanically joined together as an assembly of foodsupporting shelves which is movable with respect to said high voltageelectrodes.

6. Apparatus for smoking masses of food, comprising an ionizingstructure and a collecting structure; said ionizing structure includinga grounded metallic frame and a high voltage metallic frame insulatinglymounted on said grounded frame, said high voltage frame being connectedto the positive side of a high voltage source the negative side of whichis grounded, each of said frames having electrically connected theretoelectrodes which cooperate with those of the other frame to chargepositively with respect to ground finite particles of solid mattersuspended in the atmosphere therearound; said collecting structureincluding a grounded electrode and a high voltage electrode, said highvoltage electrode being mounted on said high voltage frame externally ofsaid ionizing structure and being electrically connected to said highvoltage frame, said grounded electrode being adapted to contact the massof food to be smoked.

7. Apparatus for smoking masses of food, comprising an ionizingstructure and a collecting structure; said ionizing structure includinga grounded metallic frame and a high voltage metallic frame insulatinglymounted on said grounded frame, said high voltage frame being connectedto the positive side of a high voltage source the negative side of whichis grounded, each of said frames having electrically connected theretoelectrodes which cooperate with those of the other frame to chargepositively with respect to ground finite particles of solid matttersuspended in the atmosphere therearound; said collecting structureincluding a plurality of spaced grounded electrodes and a plurality ofspaced high voltage electrodes intermediate said grounded electrodes,said high voltage electrodes being mounted on said high voltage frameexternally of said ionizing structure and being electrically connectedto said high voltage frame, said grounded electrodes being adapted tosupport the masses of food to be smoked.

8. Apparatus for smoking masses of food, comprising an ionizingstructure and a collecting structure; said ionizing structure includinga grounded metallic frame and a high voltage metallic frame insulatinglymounted on said grounded frame, said high voltage frame being connectedto the positive side 01' a high voltage source the negative side ofwhich is grounded, each of said frames having electrically connectedthereto electrodes which cooperate with those of the-other frame tocharge positively with respect to'ground finite particles of solidmatter suspended in the atmosphere therearound; said collectingstructure including a plurality of spaced grounded horizontally-mountedplate electrodes adapted to support said food to be smoked and aplurality of spaced high voltage horizontally-mounted plate electrodesintermediate said grounded electrodes, said high voltage electrodesbeing mounted on said high voltage frame externally of said ionizingstructure and being electrically connected to said high voltage frame.

9. Apparatus for smoking masses of food, comprising an ionizingstructure and a collecting structure; said ionizing structure includinga grounded metallic frame and a high voltage metallic frame insulatinglymounted on said grounded frame, said high voltage frame being connectedto the positive side of a high voltage source the negative side of whichis grounded, each of said frames having electrically connected theretoelectrodes which cooperate with those of the other frame to chargepositively with respect to ground finite particles of solid mattersuspended in the atmosphere therearound; said collecting structureincluding a plurality of spaced grounded horizontally-mounted plateelectrodes and a plurality of spaced high voltage horizontally-mountedplate electrodes intermediate said grounded electrodes. said highvoltage electrodes being mounted on said high voltage frame externallyof said ionizing structure and being electrically connected to said highvoltage frame, said grounded electrodes being mechanically joinedtogether as an assembly of food supporting shelves which is movable withrespect to said high voltage electrodes.

10. Apparatus for smoking masses of food, comprising an ionizingstructure and a collecting structure; said ionizing structure includinga grounded metallic frame and a high voltage metallic frame insulatinglymounted on said grounded frame, each of said frames having electricallyconnected thereto electrodes which cooperate with those of the otherframe to charge with a predetermined polarity finite particles of solidmatter suspended in the atmosphere therearound; said collectingstructure including at least one pair of spaced high voltageverticallymounted plate electrodes and including also means forsupporting a grounded mass of food intermediate said pair of electrodes.

11. Apparatus for smoking masses of food, comprising an ionizingstructure and a collecting structure; said ionizing structure includinga grounded metallic frame and a high voltage metallic frame insulatinglymounted on said grounded frame, each of said frames having electricallyconnected thereto electrodes which 00- operate with those of the otherframe to charge with a predetermined polarity finite particles of solidmatter suspended in the atmosphere therearound; said collectingstructure including at least one pair of spaced high voltageverticallymounted plate electrodes and including also means for passinga grounded mass of food between said pair of electrodes.

KENNETH W. MACKENZIE. GLENN E. ANDREWS.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,483,668 Little Feb. 12, 19241,719,354 Alsop July 2, 1929 2,225,677 White Dec. 24, 1940 2,425,652Starkey Aug. 12, 1947 2,463,422 Ransburg et a1 Mar. 1, 1949 Certificateof Correction Patent No. 2,565,454

KENNETH W. MACKENZIE ET AL.

It is hereby certified that error appears in the printed specificationof the above numbered patent requiring correction as follows:

Column 5, line 9, for smake read smoke; column 7 line 50, for inch readinch; column 9, line 16, for mattter read matter;

and that the said Letters Patent should be read as corrected above, sothat the same may conform to the record of the case in the PatentOflice.

Signed and sealed this 11th day of December, A. D. 1951.

August 21, 1951 THOMAS F. MURPHY,

Assistant Commissioner of Patents.

